Reskinning of Website theme

Well, this project is rather simple in explanation! I own a adult oriented site (which this project will NOT deal with, all work/seen content will be clean), and need the provided attachment, which is our current theme, tweaked. What do I mean by 'tweaked'? Well, We need it to look different, yet keep the same basic structure it has. That would mean altering the banners, and the colors for the most part! We need the site to look quite a bit different from it is now, for technical reasons, while not totally changing everything. Modifications of the borders, etc, etc, is fine as well, assuming I am asked before it is done so I may approve/disapprove of it before hand. :) The color theme is negotiable, but we would PREFER to stay in a darker tone, or at least a middle tone scheme, nothing bright and cheerful (or rather that makes you squint). :P